#endif
typedef struct qspinlock {
- atomic_t val;
+ union {
+ atomic_t val;
+
+ /*
+ * By using the whole 2nd least significant byte for the
+ * pending bit, we can allow better optimization of the lock
+ * acquisition for the pending bit holder.
+ */
+#ifdef __LITTLE_ENDIAN
+ struct {
+ u8 locked;
+ u8 pending;
+ };
+ struct {
+ u16 locked_pending;
+ u16 tail;
+ };
+#else
+ struct {
+ u16 tail;
+ u16 locked_pending;
+ };
+ struct {
+ u8 reserved[2];
+ u8 pending;
+ u8 locked;
+ };
+#endif
+ };
} arch_spinlock_t;
/*
* Initializier
*/
-#define __ARCH_SPIN_LOCK_UNLOCKED { ATOMIC_INIT(0) }
+#define __ARCH_SPIN_LOCK_UNLOCKED { { .val = ATOMIC_INIT(0) } }
/*
* Bitfields in the atomic value: